One of the Biggest Games in the World Is a Mod of a Mod

’Dota Auto Chess,' a mod of 'Dota 2,' which itself is based on a mod for 'Warcraft 3,' has millions of players and growing.
Dota Auto Chess
Image: Drodo Studio

Dota 2, like most video games, has you play the hero. Dota Auto Chess, a wildly popular mod of Dota 2, reimagines you as the head coach or general manager for a team of heroes. It features the same cast of characters—a dragon knight, a druid—but now you're deciding whether you have money to put them in your lineup, or whether or not they even belong in your lineup. Essentially, it’s the drafting phase of Dota 2, where you pick out what heroes you and your team will use before the game begins, spun out into its own complex, interesting game.


Just months after its release in early January, Dota Auto Chess has captivated both Dota 2 and non- Dota 2 fans. 870,233 people were playing Dota 2 concurrently at the time of writing, more than 310,000 of which are playing Dota Auto Chess. It’s only fitting that Dota Auto Chess was built as a mod to of Dota 2, a game that was originally born as a mod of another game, Warcraft III: Reign of Chaos. Like many popular mods, the success of Dota Auto Chess has been based purely on word-of-mouth; players saw their friends and peers trying out the mod and it spread from there.

Like the mod Defense of the Ancients (DotA) that came before it, Auto Chess is not just a popular new game, but one with the potential to create an entirely new genre—multiple copycats have already popped up, looking to capitalize on the game’s organic success. It's a case that perfectly shows how some of the most influential video games come not from well-funded, professional developers, but hobbyist modders who are tinkering with existing games. But it's also an exception in that it's one of the only cases where a mod of a mod found this kind of mainstream success.


Image: Drodo Studio

The original DotA had success as a mod for years before developer Valve capitalized on its popularity and released Dota 2 as a standalone game in July 2013. Dota Auto Chess, a complex, custom map inside Dota 2 created by Chinese developers Drodo Studio, has been out for just a few months and has seen a quick rise to the top—the game reportedly has more than six million registered players, up one million from just two weeks earlier. Obviously, this massive player growth has been good for Drodo Studio, but the game’s success has been good for Dota 2 as well. Since Dota Auto Chess’ release in January, concurrent players in Dota 2 have been on a steady upward trend, according to Steam Charts. Steam data compiler GitHyp reported in February that Dota 2’s player base reached its highest numbers in two years.


Dota Auto Chess has Dota and chess in its name, but it’s not all that similar to either game. Dota 2 is a competitive game where two teams of five players—all using a unique character—fight to defend their own base while attacking the other. Dota Auto Chess is more like a turn-based strategy game. Players control a Dota 2 courier, a non-playable character that delivers items in Dota 2, that pulls out the “chess pieces” onto the board, earned by spending gold and resources. Each round, players upgrade heroes using earned gold, combining multiples of the same heroes into super-versions of themselves. Drodo has even likened this aspect of Dota Auto Chess to a modded version of Mahjong, where players can use multiple tiles to create "melds." Dota 2 knowledge comes in handy when considering what each of the heroes does, and how they work together. Of course, it all takes place on your chess board, which is one of eight in a game—each of which is controlled by a different player. Games start off with players taking on neutral opponents, but players advance to taking on player enemies, too.

Each loss knocks off hit points from a counter; the last player standing after a number of rounds wins. The "chess board" playing field is merely decorative: Once a round begins, the AI-controlled heroes immediately start brawling without reference to the neat columns and rows they were placed on.

Drodo Studio developer Toto, who didn't want to share his full name, told Motherboard that the game caught on faster than expected, with its first 100,000 concurrent players racked up in just 10 days. Drodo originally expected Dota Auto Chess to be popular with people invested heavily in Dota 2, like the team itself. “But right now, we have a lot of players from other games,” Toto said.


NYU Game Center director Frank Lantz told Motherboard that Dota Auto Chess is more than just a novelty.

“It demonstrates the way that surprising new game designs and still crop up from unexpected places,” he said. “Just the fact that this was a surprising and unexpected game format that didn’t come from any of the places where big companies are spending lots of money and resources trying to develop successful game ideas, but rather came out of the culture of modding and the kinds of communities of players, designers, and tinkerers around the edges of a big, popular game… that’s great.”

It’s a similar trajectory—albeit sped up—that DotA faced. When Blizzard failed to capitalize on the success of DotA, Riot Games picked up one of the original developers and Valve signed on another to create the standalone Dota 2 game. Since then, the multiplayer online battle arena (MOBA) genre of games has taken off, and continues to sustain high numbers of players. In 2016, League of Legends developer Riot Games told Polygon it’s amassed more than 100 million monthly active players for its MOBA game. Dota 2 had more than 13 million the same month.

The history of the genre is essential in understanding exactly why Dota Auto Chess works, using the game that came before it as a base layer. Dota Auto Chess is possible because of a culture of modding that spans decades. And that culture is still shaping the way games are designed today.


“American PC game development just had as part of its ethos that when you ship a game, you also ship the engine, the tools, and the map-making capacity,” Lantz said. “You just assume that your players are also going to be making modes and maps. This culture of openness and tolls being a part of what you ship when you ship a game is what directly led to what we have now.”

Like the games that have come before, Dota Auto Chess is already moving past its humble roots as a mod of Dota 2. Drodo Studio announced earlier in March that it’ll develop a standalone version of Auto Chess, separate from Dota 2. The independent game won’t be able to use Dota 2’s characters or design, and will be on mobile platforms only. It’s not out yet, but there’s more than 832,871 pre-registrations, according to the Auto Chess website. Drodo Studio said it’ll continue to support Dota Auto Chess on PC, too. Both games will be eligible for the upcoming million dollar league with the help of Chinese media company ImbaTV.

The mobile Auto Chess version can’t use Dota 2’s characters—those are owned by Valve, and there are rules about using them commercially—so for that version, Drodo has created its own, though they do have some likeness to Dota’s characters.

“As a developer, making a mod is much easier than creating a real game,” Toto said. “There’s a lot of sources you can use, like art, story, and characters. You just need to focus on innovation—how to make your game play [well]. I think that’s the key point that makes [a] mod successful.”


Image: Drodo Studio

Without the hassle of having to generate their own art assets, Drodo could focus on the game’s design, unfolding Dota 2’s drafting phase into its own, complex format that mixes chance and skill.

“It’s like rolling dice,” Lantz said. “It’s just jolt of suspense and the feeling that you can get lucky. And sometimes do you get lucky. When you don’t, you have to play around that and it forces you to improvise. It pushes you out of the stale, repetitive loops that you might get into with a game with no randomness.”

Lantz added that the format of merging skill and luck so expertly “lends itself to experimentation,” but that it’s impossible to tell if Auto Chess can spawn a new genre of game. But games studios will try. A number of companies, including Tencent, have already filed for trademarks for “自走棋,” which translates to Auto Chess in English, according to The Esports Observer. It’s not clear if any of these trademarks are tied to Drodo Studio. But it is clear that everyone wants a piece of Auto Chess.

Dota Auto Chess’ progression to, simply, Auto Chess may be as a way to finally—and officially—monetize the game. Toto told Motherboard that Drodo Studio can’t make money directly in the Dota 2 client, since it uses Valve’s assets. In the mobile version, players will be able to purchase items called “candies” that can be used to buy stuff in game. Items purchased won’t impact game balance, however—just cosmetics. “There’s no candy store in Dota 2 right now,” Toto said. “That’s because the characters of Dota Auto Chess come from Dota 2, which is owned by Valve. Based on Valve policy, we can’t use them for commerce purposes.”

When the game was first released on Steam, however, Drodo Studio was selling candy to unlock courier skins in a roundabout way: through eBay. The team linked out players interested in customizing their couriers to an eBay page that sold codes for candy. Users could buy candy bundles at at $3, $15, and $36. The store was shut down by eBay due to negative feedback on the site, Toto said on Reddit. Candy can be earned in-game now, but there are also some third-party shops for candy around the internet, some of which are from companies who claim to be working with Drodo Studio. A representatives from German-owned Dota Auto Chess site, one of the bigger third-party candy sites, told Motherboard they partnered with Drodo and “buy[s] keys directly from them.” also advertises this on its website. Candy bundles on the site range from $6 to $128. The representative said that “around 75 percent of every sale” goes to the developer.

Motherboard also reached out to candy code distribution sites and for more information on their code supply, but neither responded. After our initial interview with Toto, Motherboard specifically asked Drodo Studio if it provided these sites with codes for candy, but we did not get a reply.

Either way, Drodo Studio is certainly benefiting from the success of the Dota 2 mod, and that success will continue with the standalone, mobile version. With such a dedicated fanbase, it's easy to forget that the mod’s only a few months old. The timeline’s sped up, but we’ve seen this trajectory before with other mods. Lantz said that Dota Auto Chess’ success is a reminder of how players collaborate in changing the shape of game design.

“It’s tempting for [professional game designers] to think of players are an audience who consume what we create,” Lantz said. “But I think it’s more appropriate to think of players as collaborators with designers. It’s a much more active form of consumption. The evolution of game design is an ongoing conversation between designers and players. The line is blurry, and that’s good.”